map_ramps contain vision blockers and dont contain blocked ramps

[tweakimp]

Currently, gameinfo.map_ramps contains vision blockers because the current ramp point condition self.placement_grid[(x, y)] == 0 and self.pathing_grid[(x, y)] == 0 is also true for them.

I think it is easier to filter them out by checking if there are different heights in these wrong Ramp objects, but maybe we can also change the ramp point condition in _find_ramps,

On the other hand, ramps that are blocked by destructable rocks are not in map_ramps.
I dont know how to find them.
We have the position of each destructable, but that is only one position, not the whole ramp.
Can we maybe get a footprint of it by its type_id?

[tweakimp]

Fixed in #275

[tweakimp]

Only partly fixed...

ramps blocked by rocks are still not counted as ramps